一个新闻系的学生,莉莉,在拍摄一部关于米德湖水位的纪录片时失踪了。当莉莉的表妹艾丽卡去寻找她时,她发现一些神秘而致命的“实体”潜伏在表面之下。A journalism student, Lilly, disappears while making a documentary about water levels at Lake Mead. When Lilly's cousin Erica goes searching for her, she comes to learn that some mysterious and deadly, \"entities\" lurk beneath the surface.